Intracellular signalling and cancer: complex pathways lead to multiple targets

Normal cells proliferate, die and differentiate as and when they should for the proper functioning of any particular tissue type. These processes are governed by a complex series of intracellular pathways that have many internal checkpoints and safety nets. These ensuring a fine, but tight, balance on overall tissue growth and distribution. A series of key aberrations, resulting in the disruption of these intracellular pathways, can lead to the development of a malignancy. The nature of these alterations is often not only tumour-specific, but also different between individuals with the same tumour type. As a result, these pathways have to be carefully dissected and functionally assessed to identify valid targets with therapeutic potential in a wide range of tumour types. (C) 2004 Elsevier Ltd. All rights reserved.